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Polyoxometalate (POM)-based lanthanide-oxo clusters (LnOCs) are a class of polynuclear lanthanide–oxygen complexes formed by polyoxometalate stabilization through oxygen bridges in which POMs can be viewed as multidentate inorganic ligands. POM-based LnOCs have received interest owing to their interesting structures and potential applications. In this paper, we summarize the classification, synthesis strategies, and properties of POM-based LnOCs. POM-based LnOCs are classified into three main categories according to their metal core element type and quantity: pure 4f clusters, 5d–4f clusters, and 3d–4f clusters. Their synthetic strategies are divided into four categories based on the source of the POM involved in the structural assembly: the lacunary POMs ligand-directed method, the in-situ transformation of lacunary POMs ligand-directed method, the in-situ generation of lacunary POMs ligand-directed method, and mixed synthesis strategies. In addition, the single-molecule magnets of POM-based LnOCs and their proton conduction properties are summarized.

The assembly of giant silver clusters by using macrocylic multidentate ligand remains a challenge. Here, the authors synthesize a chromate-templated 88-nuclei silver super calix and reveal the role of anion templating effects and a hierarchical assembly mechanism.

Summary: Radiation-processed strategy is compatible with scalable manufacturing of perovskite solar cells (PSCs). Herein, we show such radiation-processed planar negative-intrinsic-positive (n-i-p) PSCs, which integrate radiation-processed electron/hole transporting layers (ETLs/HTLs) and light-absorbing layers (LALs). Infrared radiation annealing enables SnO2 ETLs with a conductivity comparable to those annealed by hot plates and renders perovskite LALs with pure perovskite phase and prominent (111) orientation. With the benefit of chlorofullerene C60Cl6 additives for LALs, PSCs based on Li/Co-bis(trifluoromethanesulphonyl)imide (TFSI)-doped spiro-OMeTAD HTLs exhibit a champion efficiency of 22% and excellent photostability, retaining 82% of their efficiencies after 504 h of illumination. With the solar-radiation-treated gadolinium-endohedral fullerene Gd@C82-doped spiro-OMeTAD, the radiation-processed PSCs show stable efficiencies of more than 20% and decent shelf stability, maintaining 92% of their efficiencies after 1,008 h in air. Based on that prototype of radiation-processed PSCs, this work implies that cost-efficient fullerene additives/dopants are beneficial to the feasible radiation strategy for fabricating efficient and stable PSCs.

Summary: Core structures with linear, planar, and spiral conformations have been designed as triphenylamine (TPA)-based hole-transporting materials (HTMs), which are the most prevalent small molecular HTMs in perovskite solar cells (PSCs). However, most of the reported TPA-based HTMs cannot achieve sufficient balance between efficiency and stability, which is governed by core structures. Herein, a sym-penta(N,N-bis(4-methoxyphenyl)aniline)corannulene (cor-OMePTPA) featuring a corannulene core and five TPA peripheral arms is designed as alternative HTM. Planar negative-intrinsic-positive (n-i-p) PSCs with cor-OMePTPA exhibit champion efficiencies of 20% and maintain 86% of their initial performances for more than 1,000 h after thermal annealing at 60°C. Compared with spiro-OMeTAD, cor-OMePTPA-based PSCs show slightly lower efficiencies but much better thermal stabilities. The main merit of cor-OMePTPA lies in its bimolecular interpenetration capability with noncovalent interactions to modulate the HTM configurations from single-molecular curvature to bimolecular planarity, thereby providing promising opportunities to achieve excellent balance between efficiency and stability.

In the flames during low-pressure combustion, not only a rich variety of fullerenes but also many reactive intermediates can be produced (e.g., carbene, CH2) that are short-lived and cannot be stabilized directly under normal circumstances. These intermediates can be captured by fullerene carbon cages for stabilization. In this paper, three C71H2 isomers were synthesized in situ in low-pressure benzene-acetylene-oxygen diffusion flame combustion. The results, which were unambiguously characterized by single-crystal X-ray diffraction, show that the three isomers are carbene addition products of D5h-C70 on different sites. The relative energies and stability of different C71H2 isomers are revealed by Ultraviolet-Visible (UV-Vis) absorption spectroscopy, in combination with theoretical calculations, in this work. Both the in situ capture and theoretical study of these C71H2 isomers in low-pressure combustion will provide more information regarding carbene additions to other fullerenes or other carbon clusters at high temperatures.

The structures of fullerenes, or buckyballs, are often very difficult to resolve. Here, the authors describe a decapyrrylcorannulene host with ten flexible pyrryl groups that can efficiently co-crystallize with diverse fullerene derivatives in a ‘hand-ball-hand’ fashion, allowing crystallographic identification of commonly known types of fullerenes.

Unlike traditional small molecule drugs, fullerene is an all-carbon nanomolecule with a spherical cage structure. Fullerene exhibits high levels of antiviral activity, inhibiting virus replication in vitro and in vivo. In this review, we systematically summarize the latest research regarding the different types of fullerenes investigated in antiviral studies. We discuss the unique structural advantage of fullerenes, present diverse modification strategies based on the addition of various functional groups, assess the effect of structural differences on antiviral activity, and describe the possible antiviral mechanism. Finally, we discuss the prospective development of fullerenes as antiviral drugs.

Magnetic refrigeration material is the key to adiabatic demagnetization refrigeration technology. In this work, two magnetic refrigerants, Gd5(C4O4)(HCOO)3(CO3)2(OH)6·2.5H2O (1) and Gd2(OH)4SO4 (2), were prepared through hydrothermal reaction. Magnetic study reveals that their magnetic entropy changes are 24.8 J kg−1 K−1 for 1 and 15.1 J kg−1 K−1 for 2 at 2 K and 2 T, respectively. The magnetic entropy changes of 1 and 2 at T = 2 K and ∆H = 2 T exceed most gadolinium hydroxyl compounds, indicating that magnetic refrigerants with large magnetic entropy changes at low magnetic fields can be obtained by introducing more weak magnetic exchange ligands to replace hydroxyl groups in gadolinium hydroxyl compounds.

Due to the partially reduced π-conjugation of the fullerene cage, multi-functionalized fullerene derivatives exhibit remarkable fluorescent properties compared to pristine fullerenes, which have high potential for application in organic light-emitting diodes (OLEDs). In this study two multi-functionalized C70 derivatives, C70(OCH3)10[C(COOEt)2] and C70(OCH3)10[C(COOEt)2]2, with excellent fluorescence properties, were designed and synthesized. Compared with C70(OCH3)10 containing a single kind of functional group, both the C70(OCH3)10[C(COOEt)2] and C70(OCH3)10[C(COOEt)2]2 exhibited enhanced fluorescence properties with blue fluorescence emission. The fluorescence quantum yields of the C70(OCH3)10[C(COOEt)2] and C70(OCH3)10[C(COOEt)2]2 were 1.94% and 2.30%, respectively, which were about ten times higher than that of C70(OCH3)10. The theoretical calculations revealed that the multi-functionalization of the C70 increased the S1–T1 energy gap, reducing the intersystem crossing efficiency, resulting in the higher fluorescence quantum yield of the C70 derivatives. The results indicate that multi-functionalization is a viable strategy to improve the fluorescence of fullerene derivatives.

Understanding how one metal nanocluster transforms into another is of synthetic and fundamental importance. Here, the authors use mass spectrometry to reveal an acid-induced structural transformation between two Ag clusters that proceeds via a breakage-growth-reassembly mechanism.

Solar-to-chemical CO2 reduction provides a means to use light’s energy for CO2 removal and upgrading to useful products, although this photochemical conversion is challenging. Here, authors construct a Europium-containing metal-organic framework that selectively converts CO2 to formate with light.

High-nuclearity silver clusters are appealing synthetic targets for their remarkable structures, but most are isolated serendipitously. Here, the authors describe the rational use of solvents to form cluster-in-cluster silver nanowheels, which comprise an octahedral Ag6 4+ core surrounded by a Ag56 cage of unusual seven-fold symmetry.

The flash vacuum pyrolysis (FVP) technique is useful for preparing curved polycyclic aromatic compounds (PAHs) and caged nanocarbon molecules, such as the well-known corannulene and fullerene C60. However, the operating temperature of the traditional FVP apparatus is limited to ~1250 °C, which is not sufficient to overcome the high energy barriers of some reactions. Herein, we report an ultrahigh-temperature FVP (UT-FVP) apparatus with a controllable operating temperature of up to 2500 °C to synthesize fullerene C60 from a nonaromatic single carbon reactant, i.e., chloroform, at 1350 °C or above. Fullerene C60 cannot be obtained from CHCl3 using the traditional FVP apparatus because of the limitation of the reaction temperature. The significant improvements in the UT-FVP apparatus, compared to the traditional FVP apparatus, were the replacement of the quartz tube with a graphite tube and the direct heating of the graphite tube by impedance heating instead of indirect heating of the quartz tube using an electric furnace. Because of the higher temperature range, UT-FVP can not only synthesize fullerene C60 from single carbon nonaromatic reactants but sublimate some high-molecular-weight compounds to synthesize larger curved PAHs in the future.

The asymmetric unit of the title compound [Zn8(C16H12N2O4)4(H2O)4]·6C3H7NO, consists of eight ZnII cations, four tetravalent anionic ligands, L4− (L4− = 3,3′-(1E,1′E)-(ethane-1,2-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)dibenzene-1,2-bis(olate), four coordinated water molecules and six N,N-dimethylformamide solvate molecules. The coordination complex comprises an octanuclear ZnII unit with its ZnII centers coordinated in two discrete distorted square-pyramidal geometries. Four ZnII atoms each coordinate to two nitrogen atoms and two phenolate oxygen atoms from an individual L4− ligand and one coordinated water molecule. The other four ZnII atoms each bind to five phenolate oxygen atoms from three different L4− ligands. In the crystal structure, the ZnII complex unit, coordinated water molecules and dimethylformamide solvate molecules are linked via O—H...O and C—H...O hydrogen bonds. Molecules are connected by additional intermolecular O—H...O and C—H...O hydrogen bonds, forming an extensive three dimensional framework.

In the title compound, C15H8O, the asymmetric unit contains four independent molecules and crystallizes with aromatic π–π stacking interactions[centroid–centroid distances = 3.5326 (18) Å].

In the title compound, C4H3ClO3, molecules are linked via O—H...O hydrogen bonds into an infinite chain with graph-set motif C(6) along the c axis.

The molecule of the title compound, C17H10O, is nearly planar, the largest deviation from the mean plane being 0.06 Å. The crystal structure is governed by π–π interactions, with centroid–centroid distances ranging from .559 to 3.730 Å.

The sol-gel method in porous anodic aluminum oxide template is used to report the synthesis of thorium oxide and Eu-doped thorium oxide nanotubes for the first time. Strong visible light emissions are observed at low doping concentration also showing that the luminescent intensity decreases at high doping concentration.

A demonstration is presented on molten salt route in tuning of the growth directions of nanowires with specific crystal structures by using Zinc oxide (ZnO) as an example. This study deepens the understanding of the mechanism of molten-salt synthetic process, which indicates that molten salts are very effective to influence the surface energies of the crystals having polar surfaces.

A ZnO/SnO2 core-shell heterostructure is used to demonstrate the possibility of establishing a three-dimensional epitaxial interface between two materials with different crystal systems for the first time and show possible tailoring optical properties by building the heteroepitaxial crystal interface. The structural characterizations show that as-prepared ZnO/SnO2 heterostructure exhibits unique luminescence properties in contrast with individual tetrapod ZnO and SnO2 nanostructures, in which the epitaxial interface induces new luminescence properties.

The evolution of primary silica particles is studied with the use of the fluorescence-based nanosize metrology approach. It is shown that nonaggregated primary particles are present far beyond the gelation point or after prolonged aging of the silica in the presence of glycerol.

It is shown that cholesterol can bind to the intercalated bilayer, providing a route for its insertion into inorganic solids. An analysis of the alkyl chains of an intercalated bilayer is studied.

Tubular ZnO was fabricated in a microwave plasma system by using a nanowire-nanocable-nanotube scheme. A three-step route for the fabrication of ZnO is proposed.

The synthesis of fullerenes and various chlorinated carbon clusters using the glow discharge reaction, where chloroform is used as a starting reactant is studied and the characterization and separation of the reaction products is performed using the combination of high-performance liquid chromatography, ultraviolet spectrometry and mass spectrometry (HPCL-UV-MS). The results showed the involvement of the different systems of chlorinated carbon cluster intermediates during the formation of fullerenes and amorphous carbon in the glow discharge reaction of chloroform.

A systematic XRD/FTIR/CHN/ICP investigation for the structural transformation of hydrotalcite-like compounds Mg(sub 1-x)Al(sub x)(OH)(sub 2)(NO3)(sub x).nH2O as a continuous function of nitrate anions is presented. The abrupt structural changes could be caused due to the drastic change in nitrate anion arrangement even though the nitrate anion maintains its D3h symmetry.

The synthesis and the associated structural, bonding and electrochemical properties of perfluorinated fullerene C70, at the molecular level and for the bulk material are described. Expansion of the carbon frame, the elongation of the resulting C-F bond, and the presence of an ionocovalent nature could be attributed to fluorination.

The synthesis of a three dimensional framework with 35% void volume exhibiting one-dimensional channels is detailed. Single crystal x-ray analysis revealed that unprecedented hydrogen-bond-supported D(sub 2h) tetrameric cyclic water clusters formed and ranked in the channels.

A well-resolved uudd cyclic water tetramer was reported in the crystal host of [Cu(adipate)(4,4-bipyridine). (H2O)(sub 2). It showed the contribution of the water cluster to the stability of the crystal host, and the role of cooperative association of the water cluster and the crystal host in the formation of the water cluster.

Empty non-IPR fullerene ([super #11188][C.sub.72]), which is more stable than the sole IPR isomer in the fullerene[72] family, is retrieved and crystallographicaly analyzed as [super #11188][C.sub.72][Cl.sub.4]. Mass spectrometric data has supported the facile dechlorination of [super #11188][C.sub.72][Cl.sub.4] and the stability of pristine [super #11188][C.sub.72].

An operable combustion method is used for preparing non-IPR fullerene, and an octahydro[60]fullerene with a non-IPR [C.sub.60] cage produced by combustion is isolated and characterized. The studies have shown that along with chlorine, hydrogen is an ample cataloreactant for the production of non-IPR fullerene derivatives under the conditions such as arc-burning and diffusion combustion.

A new [C.sub.1]-symmetric non-IPR hollow isomer, [super #23863][C.sub.78], was captured as [super #23863][C.sub.78][Cl.sub.8] and then subjected to a regioselective substitution reaction with benzyl hydroperoxide to obtain [super #23863][C.sub.78](OOC[H.sub.2][C.sub.6][H.sub.5])[Cl.sub.7]. The differences observed in in C-Cl bond length, intermediate stability, and steric effects of the involved molecules accounted for the chemical regioselectivity of the substitution reaction.

The various mechanisms involved in the reaction taking place between Cu[Cl.sub.2] with [H.sub.2]Meppz under low temperature are discussed. The in situ C-C coupling and the formation of the heptanuclear copper(II) cluster during the reaction is also explained.

The crystal structure of Fe(tpa)[(NCS).sub.2] (tpa = tris(2-pyridylmethyl)amine) spin-crossover (SCO) complex was prepared to correlate its one-step, incomplete spin transition to its solid-state structures at different temperatures. The method to heterogeneously introduce perturbations to pre-existing supramolecular arrays of SCO units could be applied to systematic studies with an objective to discover new SCO systems and phenomenon toward their ultimate materials applications.

A chiral, cagelike high-nuclearity lanthanide hydroxide cluster containing 60 Er(III) ions is described. The cluster core has a sodalite-like structure with 24 vertex-sharing cubane-like [[[Er.sub.4][([[mu].sub.3]-OH).sub.4]].sup.8+] units and the magnetic studies have disclosed weak antiferromagnetic interactions.

The isolation and characterization of the [C.sub.56][Cl.sub.10] are described. The crystallographic data of [C.sub.56][Cl.sub.10] have shown an unusual Cl...Cl short contact and the alignment of pearl-necklace-like molecular chains, which can be converted into a class of useful one-dimensional fullerene polymer through regioselective reactions.

Dual shell-like nanoscopic magnetic clusters featuring a polynuclear nickel(II) framework encapsulating that of lanthanide ions (Ln = La, Pr, and Nd) are prepared by using Ni[(N[O.sub.3]).sub.2].6[H.sub.2]O.Ln[(N[O.sub.3]).sub.3].6[H.sub.2]O and iminodiacetic acid (IDA) under hydrothermal conditions. The magnetic properties exhibited by the structurally related cluster complexes have ranged from ferromagnetic interaction in the cluster complexes containing magnetically silent [La.sup.III] ions to the overall ferrimagnetic interactions in the assembly of this cluster type.

The evaluation of the selective encapsulation behavior of cucurbit[5]uril and its lanthanide-capped molecular capsule toward nitrate and chloride ions is discussed. Results suggest the selective inclusion of nitrate ion in the metal-free host whereas the lanthanide-capped molecular capsule prefers the inclusion of chloride ion.

The synthesis, structural characterization and magnetic studies of a gigantic mixed metal cluster consisting of 20 La(III) and 30 Ni(II) ions are described. The evaporation of the resulting blue solution under ambient conditions has afforded the product as cube-shaped blue crystals in 30% yield.

A new single chain magnet (SCM) that was prepared via a step-by-step method from a predesigned building block with an S=1 ground state is synthesized. SCM represents the first example of a compound that exhibits the coexistence of magnetization relaxation and dielectric relaxation in a SCM.

A series of polyoxometalates (POMs)-based coordination polymers are synthesized through direct incorporation between POMs and the voids of the two-dimensional (2D) network. The crystal structural analysis has shown that the relationship between the size of the void of the 2D network and that of POMs is very important for the synthesis of POMs-based open metal-organic frameworks.